Portable radio transceiver

• US 6,522,901 B1
• Filed: 03/16/2000
• Issued: 02/18/2003
• Est. Priority Date: 03/16/1999
• Status: Expired due to Term

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: Koitsalu, Evald
• Primary Examiner(s): Vo, Nguyen T.
• Assistant Examiner(s): Afshar, Kamran
• Application Number:
  US09/526,312
• Time in Patent Office: 1,069 Days
• Field of Search: 455/127, 455/73, 455/522, 455/572, 330/278, 330/277, 330/296
• US Class Current: 455/572
• CPC Class Codes: H03F 1/305 in case of switching on or off of a power supply

Abstract

A portable radio transceiver has a transmitter power amplifier (PA) and a series transistor (V1), which is connected to the transmitter power amplifier and is adapted, in response to a transmission control signal (TX on/off), to control transmission by the transmitter power amplifier. Negative bias generating means provides negative bias (V_neg) to the transmitter power amplifier and is also used for increasing a voltage applied to the gate of the series transistor so as to reduce its resistance. The negative bias generating means has a second transistor (V2) connected to the gate of the series transistor (V1), and a third transistor (V3), the gate of which is adapted to receive the transmission control signal (TX on/off) It also has a capacitor (C1) connected between the second and third transistors, and a diode means (D1) connected between the capacitor and the second transistor.

Claims

1. A portable radio transceiver, comprising a transmitter power amplifier (PA), a series transistor (V1), which is connected to the transmitter power amplifier and is adapted, in response to a transmission control signal (TX on/off), to control transmission by the transmitter power amplifier, and negative bias generating means for providing negative bias (V_neg) to the transmitter power amplifier, wherein the negative bias generating means is also used for increasing a voltage applied to the gate of the series transistor so as to reduce its resistance, characterized in that the negative bias generating means comprises:

a second transistor (V2) connected to the gate of the series transistor (V1),

a third transistor (V3), the gate of which is adapted to receive said transmission control signal (TX on/off),

a capacitor (C1) connected between the second and third transistors, and

a diode means (D1) connected between the capacitor and the second transistor.

2. A portable radio transceiver as in claim 1, wherein the negative bias (V_neg) is supplied to the transmitter power amplifier (PA) from a nods between the capacitor (C1) and the second transistor (V2).

3. A portable radio transceiver as in claim 1, wherein the series transistor (V1) is a p-channel MOSFET, whereas the second and third transistors (V2, V3) are n-channel MOSFETs.

4. A portable radio transceiver as in claim 1, wherein the transmitter power amplifier (PA) comprises at least one GaAs semiconductor component.

5. A portable radio transceiver as in claim 1, in the form of a mobile telephone.